An experimental investigation into the formation of the root and attachment apparatus in lower vertebrate tooth transplants is to be carried out. The transplants will be ectopic, autografts of tooth buds from several groups of lower vertebrates whose teeth represent the major types of tooth attachment. The major types of tooth attachment considered are: fibrous (sharks and cartilagenous fish), ankylosed (most fish, amphibians, and reptiles), hinged (Cod or Hake), and socketed (alligators, mammals, man). Advantage is to be taken of the nature of the polyphyodont dentition where at any one time all stages of tooth development are present and buds of different stages can be selected. In a previous investigation the principal investigator noted in the frog, Rana pipiens, that transplanted buds which are normally ankylosed can grow and form a complete tooth bud in an ectopic site thus defining the intrinsic (genetic) versus the extrinsic (functional) influences on the shape of the root and attachment apparatus. The present project will expand the preliminary work into an over-all investigation of the ectopic formation of the root and attachment apparatus in representative types of tooth attachments found in lower vertebrates. This project will provide further insight into a possible natural model for clinically ankylosed teeth as well provide information concerning reattachment of teeth, the nature of the attachment apparatus, and the existence of cementum in lower vertebrates.